单项选择题
下列哪一项是混杂参数（）
A．α、β、A、B B．K10、K12、K21 C．Ka、K、α、β D．t1/2、Cl、A、B E．Cl、V、α、β
单项选择题 The doctors performed a heart operation that was a miracle of medical skill.
单项选择题 My brother is a careful motorist (乘车者); he never does any dangerous driving.
单项选择题 Extensive reporting on television has helped to bring about interest in a wide variety of sports and activities.
